1. Technical Field
The present invention relates generally to a device for interrupting electrical power to an electrical appliance in response to an increase in temperature. More particularly, it relates to a device which is an electrical interface between a permanent power source and an electrical appliance and is constructed to interrupt electrical power from a conventional wall outlet to the appliance in the event that the temperature of either the appliance plug and/or the wall outlet receptacle reaches a predetermined temperature.
2. Discussion of Related Art
Devices which interrupt electrical power to an electric appliance are well known in the art. Typically, such devices are essentially circuit breakers or fuses which interrupt electrical power in the event that an electric current of a value greater than a predetermined threshold amount is delivered to the appliance. A large electrical current value relative to the requirements of a particular appliance can cause damage to the components of the appliance and may potentially create a hazardous condition. Thus, these devices typically have addressed the need to interrupt electrical power in response to a relatively large electrical current flow to an appliance.
However, such a typical fuse or circuit breaker is only responsive to electrical current and is unresponsive to the temperature condition of either the wall outlet and/or the electric appliance, specifically at the power cord plug. It has been found that an old or defective wall outlet can deteriorate to a condition which may cause the wiring of the wall outlet to reach abnormally high temperatures even with a nominal electric current flow therethrough. Such high temperature in the wiring of the wall outlet can cause arcing to occur and/or create a potential hazardous condition.
Further, some appliances, such as humidifiers, dehumidifiers, air cleaners, air conditioners, and electric heaters commonly remain plugged into a wall outlet for prolonged periods of time. In houses or buildings where the wiring is old, and as such the wiring may have deteriorated over such a period due to the heat which is generated by the appliance, the deteriorated wiring within the above mentioned wall outlet may reach abnormally high temperatures even with a nominal electric current flow therethrough creating a potentially dangerous condition.
In addition, in old or worn outlets, the plug receptacles may deteriorate to a point where the male prongs of the appliance plug may fit loosely into the female receptacles of the outlet. In appliances such as those listed above, which draw a relatively high startup current, as the appliance cycles on and off during normal use there may be some arcing at the receptacles. Arcing causes heat, and in extreme situations the male prongs may in fact melt to a point of fusing within the receptacle. As the heat increases, the potential for a hazardous condition likewise increases.
As noted above, the typical fuse or circuit breaker is only responsive to interrupt electric power to an appliance in the event of relatively high current flow therethrough. In the event of nominal current flow therethrough, the typical fuse or circuit breaker is unable to interrupt electrical power and may consequently be unable to avoid the aforementioned hazardous condition, such as overheating.
Thus, it is an object of the present invention to provide a device which interrupts electric power to an electric appliance when either the temperature of the wall outlet and/or the power cord plug of the appliance reaches a predetermined temperature.